Reinforced esophageal heat transfer devices

ABSTRACT

Reinforced esophageal heat transfer devices are disclosed. An example reinforced esophageal heat transfer device includes a distal end configured for nasopharyngeal or oropharyngeal insertion into an esophagus of a subject, a proximal end including an inlet port and an outlet port, a heat transfer region between the distal end and the proximal end, one or more lumens configured for providing a fluid path for flow of a heat transfer medium to and from the heat transfer region, and one or more reinforcing elements configured for reinforcing the one or more lumens to enable the heat transfer medium to flow through the fluid path via negative pressure.

RELATED APPLICATIONS

The present application claims priority to U.S. Provisional PatentApplication Nos. 62/477,012, filed on Mar. 27, 2017 and 62/480,842,filed on Apr. 3, 2017. The contents of each of the aforementionedapplications are incorporated herein by reference in its entirety.

TECHNICAL FIELD

The present disclosure generally relates to heat transfer devices, morespecifically, reinforced esophageal heat transfer devices; systems; andmethods for managing temperature, particularly esophageal temperatureand/or core body temperature, in a subject. In one aspect, the presenttechnology relates to a reinforced esophageal heat transfer device formanaging core body temperature in a subject. In one aspect, the presenttechnology relates to a temperature management system including areinforced esophageal heat transfer device for managing core bodytemperature in a subject. In one aspect, the present technology relatesto a method of using a reinforced esophageal heat transfer device ortemperature management system for managing core body temperature in asubject.

BACKGROUND

Active temperature management has been shown to be important for anumber of conditions. In particular, adults who remain comatose afterresuscitation from cardiac arrest, neonates suffering from hypoxicischemic encephalopathy, and patients undergoing general surgicalprocedures longer than one hour in duration all have strongrecommendations for temperature modulation. More broadly, activetemperature management has been shown to be potentially beneficial forcertain subsets of traumatic brain injury, including refractory fever inacutely brain injured patients; spinal cord injury; certain subsets ofstroke; acute myocardial infarction; traumatic/hemorrhagic cardiacarrest; surgical operations lasting longer than one hour; hepaticencephalopathy; sepsis/septic shock; and raised intracranial pressure.

For example, temperature management in an operative setting may improvepatient outcome and reduce adverse events. Oftentimes, a patient's bodytemperature is controlled while undergoing surgical procedures in anoperating room. The patient's body temperature may be controlled toavoid perioperative hypothermia during operative procedures, whichpotentially may otherwise increases the incidence of wound infection,prolong hospitalization, increase the incidence of morbid cardiac eventsand ventricular tachycardia, and/or impair coagulation. In someinstances, surface cooling (e.g., via blankets, external vests, coolinghelmets, etc.), raised operating room temperatures, inhaled gases,balloon catheters, and/or intravenous fluids are utilized to control apatient's body temperature during surgery.

Circulation of heat transfer medium (e.g., water, saline, etc.) withinan esophageal heat transfer device allows for management of core bodytemperature of a subject. External heat exchangers are used to monitorsubject temperature and adjust the temperature of circulating heattransfer medium to warm the subject, cool the subject, and/or maintainthe subject at a relatively constant temperature, such as in a state ofnormothermia. Available esophageal heat transfer devices are fabricatedfrom relatively thin-walled silicone tubing, which has a desirablecombination of heat transfer, manufacturability, and strengthproperties.

SUMMARY

The appended claims define this application. The present disclosuresummarizes aspects of the embodiments and should not be used to limitthe claims. Other implementations are contemplated in accordance withthe techniques described herein, as will be apparent to one havingordinary skill in the art upon examination of the following drawings anddetailed description, and these implementations are intended to bewithin the scope of this application.

In one aspect, the present technology pertains to a reinforcedesophageal heat transfer device. An example disclosed reinforcedesophageal heat transfer device includes a distal end configured fornasopharyngeal or oropharyngeal insertion into an esophagus of asubject, a proximal end including an inlet port and an outlet port, aheat transfer region between the distal end and the proximal end andconfigured for contacting esophageal epithelium of the subject, aflexible tube defining one or more lumens configured for providing afluid path for flow of a heat transfer medium to and from the heattransfer region, and one or more reinforcing elements, such as areinforcing wire (e.g., a coiled wire), configured for reinforcing theflexible tube to enable the heat transfer medium to flow through thefluid path via negative pressure.

In one aspect, the present technology pertains to an esophageal heattransfer device comprising at least one reinforced silicone tube. Incertain embodiments, the reinforced silicone tube comprises at least onereinforcing element. In certain embodiments, the reinforcing element isa reinforcing wire. In certain embodiments, the reinforcing element is areinforcing coil. In certain embodiments, the reinforcing coil is ametal spring, such as a stainless steel spring, a nylon spring, or aplastic spring. In certain embodiments, the reinforcing coil iscoextruded with the silicone during the formation of the tube itself. Incertain embodiments, the reinforcing coil has a substantially D-shapedcross section. In other embodiments, the reinforcing coil has a circularcross section such that the coil is substantially cylindrical. Incertain embodiments, the reinforcing coil is a light weight, lowstiffness compression spring. In certain embodiments, the reinforcingcoil has a diameter of about 1 mm to about 5 mm, preferably about 3 mm.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the invention, reference may be made toembodiments shown in the following drawings. The components in thedrawings are not necessarily to scale and related elements may beomitted, or in some instances proportions may have been exaggerated, soas to emphasize and clearly illustrate the novel features describedherein. In addition, system components can be variously arranged, asknown in the art. Further, in the drawings, like reference numeralsdesignate corresponding parts throughout the several views.

FIG. 1 is a cross-sectional side view an example heat transfer device inaccordance with the teachings herein.

FIG. 2 is a cross-sectional view the example heat transfer device ofFIG. 1.

FIG. 3A depicts another example heat transfer device in accordance withthe teachings herein.

FIG. 3B is a cross-sectional view of the heat-transfer device of FIG.3A.

FIG. 4 depicts portions of reinforcing springs extending through theheat transfer device of FIGS. 3A and 3B.

FIG. 5 further depicts a portion of one of the reinforcing springsextending through the heat transfer device of FIGS. 3A and 3B.

DETAILED DESCRIPTION

While the invention may be embodied in various forms, there are shown inthe drawings, and will hereinafter be described, some exemplary andnon-limiting embodiments, with the understanding that the presentdisclosure is to be considered an exemplification of the invention andis not intended to limit the invention to the specific embodimentsillustrated.

Oftentimes, a patient's body temperature is controlled while undergoingsurgical procedures in an operating room. The patient's body temperaturemay be controlled to avoid perioperative hypothermia during operativeprocedures, which potentially may otherwise increases the incidence ofwound infection, prolong hospitalization, increase the incidence ofmorbid cardiac events and ventricular tachycardia, and/or impaircoagulation. In some instances, surface cooling (e.g., via blankets,external vests, cooling helmets, etc.), raised operating roomtemperatures, inhaled gases, balloon catheters, and/or intravenousfluids are utilized to control a patient's body temperature duringsurgery.

In one aspect, the present technology pertains to a reinforcedesophageal heat transfer device. Example reinforced esophageal heattransfer devices include a heat transfer region that is configured forcontacting tissue (e.g., esophageal epithelium) of a subject andtransferring heat to the esophageal epithelium to heat or cool thesubject. In certain embodiments, the reinforced esophageal heat transferdevices include a distal end configured for nasopharyngeal ororopharyngeal insertion into an esophagus of the subject and a proximalend that includes an inlet port and an outlet port. In some suchembodiments, the heat transfer region is located between the distal endand the proximal end. Further, an example reinforced esophageal heattransfer device includes a plurality of lumens (e.g., a heat transfermedium supply lumen, a heat transfer medium return lumen) that areconfigured for providing a fluid path for flow of a heat transfer mediumto and from the heat transfer region. Example reinforced esophageal heattransfer devices include a reinforcing element. For example, a pluralityof reinforcing wires are configured for reinforcing a flexible tube thatdefines the plurality of lumens to enable the heat transfer medium toflow through the fluid path via negative pressure. That is, the examplereinforced esophageal heat transfer devices are reinforced with theplurality reinforcing wires to prevent the negative pressure fromcollapsing the flexible tube and, thus, maintain the patency of thefluid path.

In certain embodiments, the reinforcing element is integrated with thedevice and, in particular, the flexible tube(s) defining a lumen forflow of heat transfer medium. For example, the reinforcing element maybe coextruded with the tubing during the formation of the tube itself.In certain embodiments, the reinforcing element is a separate componentfrom the device. For example, the reinforcing element may be disposedwithin the lumen.

In certain embodiments disclosed herein, a reinforced esophageal heattransfer device is intended to control a subject's temperature, whilesimultaneously maintaining access to the stomach to allow gastricdecompression and drainage. In some such embodiments, the esophagealheat transfer device comprises a silicone tube with three lumens. Insome such embodiments, two parallel lumens (an inflow lumen and anoutflow lumen) are in fluid communication with each other and anexternal heat exchanger to provide a fluid path for the flow of heattransfer medium to and from the external heat exchanger. In some suchembodiments, a third lumen provides gastric access. The third lumen canbe connected to wall suction and used for standard gastricdecompression. In certain embodiments, the third lumen is in a co-axialarrangement with the inflow and outflow lumens. In some suchembodiments, a web supports the inner gastric lumen and separates inflowand outflow lumens. Upon placement in a subject, an external portion ofthe silicone tube is in contact with the esophageal tissue of thesubject. Modulation and control of subject temperature is intended to beachieved by connecting the device to an external heat exchanger andcirculating temperature-controlled heat transfer medium (e.g., water)along the fluid path.

In one aspect, the present technology pertains to an esophageal heattransfer device comprising at least one reinforced silicone tube. Incertain embodiments, the reinforced silicone tube comprises at least onereinforcing element. The reinforcing element enhances the radialstiffness of the tube sufficiently to prevent the collapsing of the tubewhen operating in a negative pressure environment and/or enhanceslongitudinal stiffness of the tube to enhance placement. In certainembodiments, the reinforcing element is a light weight, low stiffnesscompression spring. In certain embodiments, the spring is a metalspring. In certain embodiments, the metal is non-ferromagnetic metal. Incertain embodiments, one or more such springs are disposed within atleast one lumen of the esophageal heat transfer device (i.e., multiplesprings may be present in each lumen). In certain embodiments, a singlespring is coextruded to maintain the stiffness of the tube. In certainembodiments, an exemplary esophageal heat transfer device comprisesthree lumens: inflow lumen, outflow lumen, and central lumen. In somesuch embodiments, at least one reinforcing element is disposed within atleast one of the lumens. In some such embodiments, the reinforcingelement is a reinforcing wire, such as metal spring. In some suchembodiments, a first metal spring is disposed within the inflow lumenand a second metal spring is disposed within the outflow lumen. In somesuch embodiments, a first set of metal springs are disposed withininflow lumen and a second set of metal springs are disposed within theoutflow lumen. The first set of metal springs can be arranged inparallel to each other. Likewise, the second set of metal springs can bearranged in parallel to each other. In some such embodiments, extensiontubes are provided to connect the heat transfer device to an externalheat exchanger.

In certain embodiments, an esophageal heat transfer device comprising atleast one reinforced silicone tube has an increased radio-opacityrelative to existing esophageal heat transfer devices. As such, anesophageal heat transfer device comprising at least one reinforcedsilicone tube may be viewed using x-ray imaging.

In certain embodiments, the reinforcing element is integrated with thedevice and, in particular, the silicone tube. For example, thereinforcing element may be coextruded with the silicone during theformation of the tube itself. In certain embodiments, the reinforcingelement is a separate component from the device. For example, thereinforcing element may be disposed within the lumen of the siliconetube.

In one aspect, the present technology pertains to a system to managetemperature in a subject, the system including: an esophageal heattransfer device comprising at least one reinforced silicone tube and asource of a heat transfer medium. The esophageal heat transfer device iscapable of interconnection to the source of the heat transfer medium.The source of the heat transfer medium operates to circulate the heattransfer medium through the heat transfer device. In certainembodiments, the source of the heat transfer medium includes areservoir. In certain embodiments, the reservoir is capable of storingthe heat transfer medium. In certain embodiments, the system includesthe esophageal heat transfer device comprising at least one reinforcedsilicone tube and a negative pressure chiller, such as the Arctic SunTemperature Management System (Bard Medical) or equivalent unit

In certain embodiments, the esophageal heat transfer device comprisingat least one reinforced silicone tube is used with a negative pressurechiller, such as the Arctic Sun Temperature Management System (BardMedical) or equivalent unit. In certain other embodiments, theesophageal heat transfer device comprising at least one reinforcedsilicone tube is used with another source of heat transfer medium suchas a Medi-Therm III Conductive Hyper/Hypothermia System(Gaymar/Stryker), a Blanketrol II or Blanketrol III Hyper-HypothermiaSystem (Cincinnati Sub-Zero) or equivalent unit.

In certain embodiments, the source of the heat transfer medium suppliestemperature-controlled fluid, such as water or saline, through aconnector hose to the heat transfer device. An accessory temperatureprobe may interface between the source and the subject to sense subjecttemperature, which may be displayed on the source's control panel. Incertain embodiments, the source includes a circulating pump, heater, andrefrigeration system.

In certain embodiments, the system further comprises a subjecttemperature probe. In certain embodiments, the source of the heattransfer medium interfaces with a subject temperature probe. The subjecttemperature probe can be a component of the heat transfer device or aseparate device that is capable of being directly or indirectly coupledto the source. Subject temperature probes are commercially availablefrom, for example, Smiths Medical. Subject temperature probes areavailable for rectal, oral, vaginal, esophageal, or bladder temperaturemeasurement.

In certain embodiments, the system includes: (a) at least one processor;(b) at least one operator interface configured to provide input to theprocessor; and (c) at least one memory. The system is configured to: (1)receive an operator generated temperature setting and (2) control thetemperature of the heat transfer medium and/or the flow rate of heattransfer medium through the heat transfer device.

In certain embodiments, the system senses a temperature of the subject(e.g., core body temperature of the subject) through a temperature probeand compares it to a user-selected target temperature, adjusting thetemperature and/or flow rate of the heat transfer medium appropriately.For example, a temperature probe may convert subject temperature datainto electronically readable signals that are transmitted to the sourceof the heat transfer medium, which then, if necessary, automaticallyadjusts the temperature and/or flow rate of the heat transfer medium toachieve target temperature.

In certain embodiments, the reinforcing element enhances radialstiffness of the tube sufficiently to prevent the collapsing of the tubewhen operating under negative pressure. In certain embodiments, thereinforcing element additionally provides longitudinal stiffness to thedevice. The additional longitudinal stiffness provided by thereinforcing element allows for easier placement of the device. Incertain embodiments, the reinforcing element provides sufficientlongitudinal stiffness to facilitate insertion and placement of thedevice, but also includes sufficient flexibility to facilitate traversalof the subject's pharynx and esophagus from an access point, such as thesubject's mouth or nostril. In certain embodiments, the term “subject”includes a mammal in need of therapy for a condition, disease, ordisorder or the symptoms associated therewith. The term “subject”includes dogs, cats, pigs, cows, sheep, goats, horses, rats, mice andhumans. The term “subject” does not exclude an individual that is normalin all respects.

In certain embodiments, the subject is in need of targeted temperaturemanagement. In certain embodiments, the subject is febrile. In some suchembodiments, the subject is in an intensive care unit. In certainembodiments, the subject is suffering from or is at risk of suffering anischemia-reperfusion injury.

In certain embodiments, the subject presents with out-of-hospitalcardiac arrest (OHCA). In certain embodiments, the subject presents within-hospital cardiac arrest (IHCA). In certain embodiments, the subjecthas been resuscitated following cardiac arrest. In some suchembodiments, the subject's core body temperature is maintained betweenabout 33° C. and about 36° C., such as about 33° C., about 34° C., about35° C., or about 36° C., for at least 12 hours. Alternatively, thesubject's core body temperature is maintained between about 33° C. andabout 36° C. for at least 24 hours, at least 36 hours, at least 48hours, at least 60 hours, at least 72 hours, at least 84 hours, or atleast 96 hours.

In certain embodiments, the subject has hypoxic ischemic encephalopathy.In some such embodiments, the subject's core body temperature ismaintained between about 32° C. and about 34° C., such as about 32° C.,about 33° C., or about 34° C., for at least 24 hours. Alternatively, thesubject's core body temperature is maintained between about 32° C. andabout 34° C. for at least 48 hours, at least 72 hours, or at least 96hours.

In certain embodiments, the subject has suffered a neurological insult,such as a stroke, spinal cord injury, or traumatic brain injury. In somesuch embodiments, the subject's core body temperature is maintained atnormothermia for at least 24 hours. Alternatively, the subject's corebody temperature is maintained at normothermia for at least 48 hours, atleast 72 hours, or at least 96 hours.

In certain embodiments, the subject has suffered an acute myocardialinfarction. In some such embodiments, the subject's core bodytemperature is maintained between about 33° C. and about 36° C., such asabout 33° C., about 34° C., about 35° C., or about 35° C., for at least12 hours. Alternatively, the subject's core body temperature ismaintained between about 33° C. and about 36° C. for at least 24 hours,at least 36 hours, at least 48 hours, at least 60 hours, at least 72hours, at least 84 hours, or at least 96 hours.

In certain embodiments, the subject is a burn patient. In some suchembodiments, the burn patient is undergoing a surgical procedure. Insome such embodiments, the burn patient's core body temperature ismaintained at normothermia for the duration of the surgical procedure.In some such embodiments, the burn patient's core body temperature ismaintained within a target range for the duration of the surgicalprocedure.

In certain embodiments, the subject is a patient undergoing a surgicaloperation. In some such embodiments, the surgical operation is scheduledto last for more than one, two, three, four, five, six, seven, or eighthours. In a particular embodiment, the surgical operation is scheduledto last for at least one hour. In some such embodiments, the subject'score body temperature is maintained at normothermia for the duration ofthe surgical operation. In some such embodiments, the subject's corebody temperature is maintained within a target range for the duration ofthe surgical operation.

Turning to the figures, FIGS. 1 and 2 depict an exemplary reinforcedheat transfer device 100 in accordance with the teachings herein. Morespecifically, FIG. 1 is a cross-sectional side view of the reinforcedheat transfer device 100, and FIG. 2 is a cross-sectional view of theheat transfer region of the reinforced heat transfer device 100.

As illustrated in FIG. 1, the reinforced heat transfer device 100includes a heat transfer region 102, which includes an internal cavity104. The reinforced heat transfer device 100 includes a proximal end 106and a distal end 108. The heat transfer region 102 extends between theproximal end 106 and the distal end 108. The reinforced heat transferdevice 100 also includes an inlet port 110 and an outlet port 112. Theinlet port 110 is fluidly connected to a heat transfer medium supplylumen 114 of the reinforced heat transfer device 100, and the outletport 112 is fluidly connected to a heat transfer medium return lumen 116of the reinforced heat transfer device 100.

As illustrated in FIG. 2, the reinforced heat transfer device 100includes a wall 118 that divides the internal cavity 104 into amulti-lumen cavity including the heat transfer medium supply lumen 114and the heat transfer medium return lumen 116. The heat transfer mediumsupply lumen 114 and the heat transfer medium return lumen 116 are influid communication with each other, thereby defining a fluid path forflow of a heat transfer medium through the reinforced heat transferdevice 100. For example, the wall 118 extends from the proximal end 106and toward, but not to, the distal end 108 such that the heat transfermedium supply lumen 114 and the heat transfer medium return lumen 116fluid connected toward the distal end 108 of the reinforced heattransfer device 100.

Returning to FIG. 1, the inlet port 110 is configured to connect to aninflow tube 120, and the outlet port 112 is configured to connect to anoutflow tube 122. For example, the inflow tube 120 and the outflow tube122 are coupled to an external source (e.g., a heat exchanger configuredto heat or chill a heat transfer medium). The inflow tube 120 defines anexternal supply lumen that provides a fluid path for flow of the heattransfer medium from the heat exchanger and to the heat transfer mediumsupply lumen 114 of the reinforced heat transfer device 100. The outflowtube 122 defines an external return lumen that provides a fluid path forflow of the heat transfer medium from the heat transfer medium returnlumen 116 of the reinforced heat transfer device 100 to the externalsource.

When the external source is a heat exchanger, the heat exchanger may beany of a variety of conventionally designed heat exchangers. Forexample, the heat exchanger may operate to provide the heat transfermedium via negative pressure. The heat transfer medium may be a gas,such as, for example, nitrous oxide, Freon, carbon dioxide, or nitrogen.Alternatively, the heat transfer medium may be a liquid, such as, forexample, water, saline, propylene glycol, ethylene glycol, or mixturesthereof. In other embodiments, the heat transfer medium may be a slurry,such as, for example, a mixture of ice and salt. In still otherembodiments, the heat transfer medium may be a gel, such as, forexample, a refrigerant gel. Alternatively, the heat transfer medium maybe a solid, such as, for example, ice or a heat conducting metal. Inother embodiments, the heat transfer medium may be formed, for example,by mixing a powder with a liquid. Thus, it should be understood thatcombinations and/or mixtures of the above-mentioned media may beemployed to achieve a heat transfer medium according to the presenttechnology.

Thus, the inflow tube 120 and the outflow tube 122 fluidly connect theheat exchanger and the reinforced heat transfer device 100 to enable theheat transfer medium to flow between the heat exchanger and thereinforced heat transfer device 100 to heat or cool the reinforced heattransfer device 100. For example, when the inflow tube 120 is coupled tothe inlet port 110 and the outflow tube 122 is coupled to the outletport 112, the heat transfer medium flows from the heat exchanger,through the inflow tube 120 and into the heat transfer medium supplylumen 114 to heat or cool a subject via the heat transfer medium.Further, the heat transfer medium flows from the heat transfer mediumsupply lumen 114, through the heat transfer medium return lumen 116, andto the outflow tube 122 to circulate the heat transfer medium back tothe heat exchanger.

Additionally, the reinforced heat transfer device 100 is configured forplacement within an anatomical structure of a mammalian subject. Thedistal end 108 of the reinforced heat transfer device 100 is configuredfor insertion into a body orifice. For example, the distal end 108 ofthe reinforced heat transfer device 100 is configured for insertion intothe nostrils, mouth, anus, or urethra of a subject. When properlyinserted, the distal end 108 of the reinforced heat transfer device 100may be ultimately positioned in the esophagus, rectum, colon, bladder,or other anatomical structure. Upon insertion of the reinforced heattransfer device 100 into a subject (e.g., via nostrils, mouth, anus, orurethra), a heat transfer region 102 of the reinforced heat transferdevice 100 may directly contact an epithelial surface of the subject.For example, when the reinforced heat transfer device 100 is insertedinto an esophagus of the subject, at least a portion of the heattransfer region 102 directly contacts the esophageal epithelium of thesubject. For example, the heat transfer region 102 may comprise flexibletubing 124 and is generally located between the distal end 108 and theproximal end 106. In other examples, the heat transfer region 102 isdefined by the flexible tubing 124 and the distal end 108 of thereinforced heat transfer device 100. The heat transfer medium issupplied to the reinforced heat transfer device 100 (e.g., from a heatexchanger) via the inlet port 110 and the inflow tube 120 connected tothe inlet port 110. The heat transfer medium circulates through thereinforced heat transfer device 100 to transfer heat (e.g., to heat, tocool, or to maintain temperature) between the subject and the heattransfer region 102 that contacts and/or is positioned adjacent to aninner surface (e.g., of the esophagus) of the subject. Further, the heattransfer medium exits the reinforced heat transfer device 100 throughthe outlet port 112 and the outflow tube 122 connected to the outletport 112.

As illustrated in FIGS. 1 and 2, the reinforced heat transfer device 100also includes a gastric access tube 126 that defines a gastric accesslumen 128 and extends to the distal end 108 of the reinforced heattransfer device 100. Further, the reinforced heat transfer device 100includes one or more ports 130 along the side of the gastric access tube126. In the illustrated example, the one or more ports 130 are locatedalong the gastric access tube 126 at the distal end 108 of thereinforced heat transfer device 100. The one or more ports 130 mayprovide for communication between the space exterior to the reinforcedheat transfer device 100 and the gastric access lumen 128. For example,the one or more ports 130 may act as a portal between the subject'sstomach and the gastric access lumen 128 allowing the gastric contentsto be suctioned from the subject's stomach out through the gastricaccess lumen 128. The presence of one or more ports 130 provides reducedlikelihood of blockage of the gastric access lumen 128 from semi-solidstomach contents. Alternatively, multiple gastric access lumens may beemployed. The addition of one or more ports 130 may improve and enhancethe removal of stomach contents, which, in turn, may improve contactbetween gastric mucosa and the heat transfer region 102 of thereinforced heat transfer device 100. Such improved contact may enhanceheat transfer between the reinforced heat transfer device 100 and thegastric mucosa and, thus, enhance heating or cooling of the subject. Theconfiguration of the ports 130 shown in FIG. 1 is oval. However, theports 130 can be, for example, circular, rectangular, or any other shapethat permits flow of gastric contents from the stomach to the gastricaccess lumen 128.

The reinforced heat transfer device 100 is manufactured via, forexample, extrusion. For example, utilizing extrusion processes to formthe reinforced heat transfer device 100 may eliminate the need to sealjunctions or affix end caps and reduce the points at which leaks mayoccur. In some examples, the flexible tubing 124, the wall 118, and thegastric access tube 126 are integrally formed via extrusion. In otherexamples, the flexible tubing 124 and the wall 118 are integrally formedvia extrusion, the gastric access tube 126 is formed separately viaextrusion, and the gastric access tube 126 is subsequently inserted intothe internal cavity 104 defined by the flexible tubing 124. In otherexamples, the flexible tubing 124, the wall 118, and the gastric accesstube 126 are formed separately via extrusion, and the wall 118 and thegastric access tube 126 are inserted into the internal cavity 104 toassemble the reinforced heat transfer device 100.

In some examples, components of the reinforced heat transfer device 100(e.g., the flexible tubing 124, the wall 118, and the gastric accesstube 126) includes or is formed of a semi-rigid material such as asemi-rigid polymer. For example, the flexible tubing 124, the wall 118,and/or the gastric access tube 126 is formed of silicone to increase aflexibility and/or a thermal conductivity of the reinforced heattransfer device 100. In some such examples, the components of thereinforced heat transfer device 100 are formed of biomedical gradeextruded silicone rubber such as Dow Corning Q7 4765 silicone. When theflexible tubing 124 is formed of silicone, the heat transfer region 102defined by the flexible tubing 124 more efficiently transfers heat fromthe heat transfer medium to the esophageal epithelium to heat or coolthe subject due to the increased thermal conductivity of the materialforming the reinforced heat transfer device 100. In other examples, thecomponents of the reinforced heat transfer device 100 are formed ofother semi-rigid materials including semi-rigid plastics such asethylene tetrafluoroethylene (ETFE), polytetrafluoroethylene (PTFE),perfluoroalkoxy (PFA), and fluorinated ethylene propylene (FEP).

In certain embodiments, the reinforced heat transfer device 100 of theillustrated example includes one or more reinforcing elements disposedwithin one or more lumens, such as an inflow lumen and/or an outflowlumen.

In certain embodiments, the reinforced heat transfer device 100 of theillustrated example includes one or more reinforcing elements, such as areinforcing wire (e.g., mesh, coil), embedded into the flexible tubing124, the wall 118, and/or the gastric access tube 126 of the reinforcedheat transfer device 100. For example, a reinforcing wire may beembedded into one or more of the components of the reinforced heattransfer device 100 during the extrusion process. The reinforcing wiremay be a metallic wire that stiffens the reinforced heat transfer device100. In some such embodiments, the reinforcing wires form a meshembedded in the flexible tubing 124, a mesh embedded in the wall 118,and/or a mesh embedded in the gastric access tube 126 of the toreinforce the semi-rigid material of the reinforced heat transfer device100. In other examples, the reinforcing wires may be springs (e.g.,helical springs such as 5-millimeter helical springs, D-shaped springs)that are embedded in the flexible tubing 124, the wall 118, and/or thegastric access tube 126 to reinforce or stiffen the reinforced heattransfer device 100.

In certain embodiments, the reinforced heat transfer device 100 includesa reinforcing element, such as a reinforcing wire, to prevent the fluidpath from becoming blocked when a negative pressure is applied to theheat transfer medium supply lumen 114 and/or the heat transfer mediumreturn lumen 116.

For example, the heat transfer device 100 may be fluidly connected to aheat exchanger via the inlet port 110 and the outlet port 112 to enablethe heat transfer device 100 to transfer heat to heat or cool thesubject. In some examples, the heat exchanger provides the heat transfermedium to the heat transfer device 100 by creating a negative pressure.In some instances, when the flexible tubing 124, the wall 118, and/orthe gastric access tube 126 defining the heat transfer medium supplylumen 114 and/or the heat transfer medium return lumen 116 are formed ofsilicone rubber and/or any other semi-rigid material without areinforcing element, the negative pressure generated by the heatexchanger potentially may cause the flexible tubing that defines theheat transfer medium supply lumen 114 and/or the heat transfer mediumreturn lumen 116 to collapse. In such instances, the heat transfermedium is unable to flow through the fluid path defined by the heattransfer medium supply lumen 114 and the heat transfer medium returnlumen 116 and, thus, is unable to cause heat to transfer to the subjectvia the heat transfer region 102.

The reinforcing element of the heat transfer device 100 serves tostiffen and/or otherwise reinforce the flexible tubing 124, the wall118, and/or the gastric access tube 126 to prevent the heat transfermedium supply lumen 114 and the heat transfer medium return lumen 116from collapsing when negative pressure is created by the heat exchangerfluidly connected to the heat transfer device 100. That is, thereinforcing element facilitates flow of the heat transfer medium throughthe fluid path of the heat transfer device 100 when utilized with anexternal heat exchanger that provides heat transfer medium via negativepressure, thereby enabling the heat transfer device 100 to be utilizedwith such heat exchangers to warm or cool a subject.

In certain embodiments, a reinforcing element, such as one formed ofmetallic material(s), increases radio-opacity of the heat transferdevice 100. For example, the increased radio-opacity enables the heattransfer device 100 to be viewed via an x-ray when inserted into theesophagus of the subject. By enabling the heat transfer device 100 to beviewed via an x-ray, the reinforcing element enables an operator (e.g.,a technician, a nurse, a doctor) to utilize an x-ray to determine alocation of and/or to navigate the heat transfer device 100 wheninserted into the subject.

FIGS. 3A, 3B, 4, and 5 illustrate another example heat transfer device300 in accordance with the teachings herein. More specifically, FIG. 3depicts the heat transfer device 300 when assembled, FIG. 4 depicts across-sectional top view of the heat transfer device 300, FIG. 5 depictsa portion of the heat transfer device 300 when partially disassembled,and FIG. 6 depicts a portion of the heat transfer device 300 whenpartially assembled.

As illustrated in FIGS. 3A and 3B, the heat transfer device 300 includesthe heat transfer region 102, the proximal end 106, the distal end 108,the inlet port 110, the outlet port 112, the wall 118, and the gastricaccess tube 126. Those components of the heat transfer device 300 areidentical to or substantially similar to the heat transfer region 102,the proximal end 106, the distal end 108, the inlet port 110, the outletport 112, the wall 118, and the gastric access tube 126 as disclosed inaccordance with FIGS. 1-2. Accordingly, some features of thosecomponents of the heat transfer device 300 will not be described infurther detail below.

The heat transfer device 300 includes one or more reinforcing elements302 that extend through the internal cavity 104 to reinforce or stiffenthe heat transfer device 300. In certain embodiments, the reinforcingelement(s) 302 are metallic wires that stiffen the reinforced heattransfer device 300. As illustrated in FIG. 3A, one or more of thereinforcing elements 302 extend through the inlet port 110 and/or intothe inflow tube 120 to reinforce at least a portion of the inflow tube120. One or more of the reinforcing elements 302 also extend through theoutlet port 112 and/or into the outflow tube 122 to reinforce at least aportion of the outflow tube 122.

As illustrated in FIG. 3B, one or more of the reinforcing elements 302are inserted into the heat transfer medium supply lumen 114 to reinforcethe heat transfer medium supply lumen 114 to prevent the heat transfermedium supply lumen 114 from collapsing when a negative pressure isapplied. Further, one or more of the reinforcing elements 302 areinserted into the heat transfer medium return lumen 116 to reinforce theheat transfer medium return lumen 116 to prevent the heat transfermedium return lumen 116 from collapsing when a negative pressure isapplied. In the illustrated example, two of the reinforcing elements 302are inserted into the heat transfer medium supply lumen 114, and two ofthe reinforcing elements 302 are inserted into the heat transfer mediumreturn lumen 116. In other examples, more or less of the reinforcingelements 302 may be inserted into the heat transfer medium supply lumen114 and/or the heat transfer medium return lumen 116 to stiffen the heattransfer device 300. Further, in some examples, one or more of thereinforcing elements 302 are inserted into the gastric access lumen 128.

In the illustrated example, the reinforcing elements 302 are springs,such as helical springs (e.g., 5-millimeter helical springs) or D-shapedsprings. In other examples, the reinforcing elements 302 are meshes thatextend through the internal cavity 104 of the heat transfer device 300.Further, in the illustrated example, the flexible tubing 124, the wall118, and/or the gastric access tube 126 are not embedded withreinforcing wires such that the reinforcing elements 302 inserted intothe internal cavity 104 to prevent the flexible tubing 124, the wall118, and/or the gastric access tube 126 from collapsing. In otherexamples, other reinforcing elements (e.g., a reinforcing wire) areembedded into the flexible tubing 124, the wall 118, and/or the gastricaccess tube 126 such that the reinforcing element and the embeddedreinforcing wires combine to reinforce the fluid path of the heattransfer device 300.

FIG. 4 illustrates a portion of the heat transfer device 300 when a portconnector 402 of the heat transfer device 300 is decoupled from theflexible tubing 124. As illustrated in FIG. 4, the port connector 402includes the inlet port 110, the outlet port 112, an aperture 404through which the gastric access tube 126 is to extend, and an end 406that is to couple to the flexible tubing 124. In the illustratedexample, two reinforcing elements 302 extend through the heat transfermedium supply lumen 114. Additionally, two reinforcing elements 302extend through the heat transfer medium return lumen 116.

FIG. 5 illustrates a portion of the heat transfer device 300 when theport connector 402 is coupled to the flexible tubing 124 of the heattransfer device 300. In the illustrated example, one reinforcing element302 extends through the heat transfer medium return lumen 116, throughthe outlet port 112, and at least partially into the outflow tube 122.

Additional Embodiments

In one aspect, the present disclosure provides an esophageal heattransfer device comprising at least one reinforced tube defining a lumenfor flow of a heat transfer medium. In certain embodiments, thereinforced tube is a silicone tube.

In one aspect, the present disclosure provides an esophageal heattransfer device comprising a lumen for flow of a heat transfer mediumand a reinforcing element disposed within said lumen. In certainembodiments, the reinforcing element is a coil, preferably a spring, andmore preferably a metal spring.

In one aspect, the present disclosure provides an esophageal heattransfer device comprising a first reinforced tube defining an inflowlumen and a second reinforced tube defining an outflow lumen. In certainembodiments, the first and second reinforced tubes have sufficientradial strength to prevent collapse in a negative pressure environment.

In one aspect, the present disclosure provides an esophageal heattransfer device comprising an inflow lumen in fluid communication withan outflow lumen, and at least one reinforcing element disposed withinsaid inflow lumen or said outflow lumen. In certain embodiments, atleast one reinforcing element is disposed within each of said inflowlumen and said outflow lumen.

In one aspect, the present disclosure provides a reinforced esophagealheat transfer device comprising: (a) a distal end configured fornasopharyngeal or oropharyngeal insertion into an esophagus of asubject; (b) a proximal end including an inlet port and an outlet port;(c) a heat transfer region between the distal end and the proximal end;(d) one or more lumens configured for providing a fluid path for flow ofa heat transfer medium to and from the heat transfer region; and (e) oneor more reinforcing elements configured for reinforcing the one or morelumens to enable the heat transfer medium to flow through the fluid pathvia negative pressure.

In this application, the use of the disjunctive is intended to includethe conjunctive. The use of definite or indefinite articles is notintended to indicate cardinality. In particular, a reference to “the”object or “a” and “an” object is intended to denote also one of apossible plurality of such objects. Further, the conjunction “or” may beused to convey features that are simultaneously present instead ofmutually exclusive alternatives. In other words, the conjunction “or”should be understood to include “and/or”. The terms “includes,”“including,” and “include” are inclusive and have the same scope as“comprises,” “comprising,” and “comprise” respectively.

The above-described embodiments, and particularly any “preferred”embodiments, are possible examples of implementations and merely setforth for a clear understanding of the principles of the invention. Manyvariations and modifications may be made to the above-describedembodiment(s) without substantially departing from the spirit andprinciples of the techniques described herein. All modifications areintended to be included herein within the scope of this disclosure andprotected by the following claims.

1. An esophageal heat transfer device comprising at least one reinforcedtube defining a lumen for flow of a heat transfer medium.
 2. Theesophageal heat transfer device of claim 1, wherein the at least onereinforced tube is a silicone tube.
 3. The esophageal heat transferdevice of claim 1, further comprising a reinforcing element disposedwithin said lumen.
 4. The esophageal heat transfer device of claim 1,further comprising a reinforcing element integral with the at least onereinforced tube defining said lumen.
 5. The esophageal heat transferdevice of claim 4, wherein the reinforcing element is a coiled wire. 6.The esophageal heat transfer device of claim 1, wherein the at least onereinforced tube defines at least one of an inflow lumen and an outflowlumen.
 7. The esophageal heat transfer device of claim 1, wherein thereinforced tube is configured to have a radial strength that is toprevent collapse in a negative pressure environment.
 8. A reinforcedesophageal heat transfer device comprising: a distal end configured fornasopharyngeal or oropharyngeal insertion into an esophagus of asubject; a proximal end including an inlet port and an outlet port; aheat transfer region between the distal end and the proximal end; one ormore lumens configured for providing a fluid path for flow of a heattransfer medium to and from the heat transfer region; and one or morereinforcing elements configured for reinforcing the one or more lumensto enable the heat transfer medium to flow through the fluid path vianegative pressure.
 9. The reinforced esophageal heat transfer device ofclaim 8, wherein at least one of the one or more reinforcing elements isdisposed within at least one lumen.
 10. The reinforced esophageal heattransfer device of claim 8, wherein at least one of the one or morereinforcing elements is integral with a tube defining at least onelumen.
 11. The reinforced esophageal heat transfer device of claim 8,wherein at least one of the one or more reinforcing elements is a coiledwire.
 12. A method for controlling core body temperature in a subject inneed thereof, the method comprising the steps of: providing a heattransfer device, the heat transfer device comprising a heat transferregion having at least one reinforced tube defining a lumen, said lumenproviding a fluid path for flow of a heat transfer medium; placing theheat transfer region of the heat transfer device in an esophagus of thesubject; and initiating flow of the heat transfer medium along the fluidpath.
 13. The method of claim 12, wherein at least one reinforcingelement is disposed within said lumen.
 14. The method of claim 12,wherein at least one reinforcing element is integral with the tubedefining said lumen.
 15. The method of claim 12, wherein the heattransfer medium is circulated along the fluid path via negativepressure.
 16. The esophageal heat transfer device of claim 3, whereinthe reinforcing element is a coiled wire.